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Foreign Law Research for U.S. Attorneys

An introductory guide to finding the laws of foreign jurisdictions.

What is Foreign Law?

Foreign law is the domestic law of a country other than your own. For example, Mexican and Chinese law are foreign law for  a U.S. attorney; Chinese and U.S. law are foreign law for a Mexican attorney; and Mexican and U.S. law are foreign law for a Chinese attorney.

Foreign law is distinguished from international law, which governs relationships between different countries and between individuals from different countries. 

The guide provides basic information on how to research foreign law for U.S. attorneys.

Tips for Foreign Law Research

Always start with a guide. Because of the variation in legal systems and legal sources between countries, you should always start with a guide to researching the law of your country.

Don't commit unauthorized practice of law. Passing the bar in California does not give you the right to practice law in Arizona, let alone Mexico. Unless you are licensed to practice law in another country, your foreign law research should generally be limited to academic research and learning enough to work intelligently with local counsel. 

Don't expect to have access to non-U.S. law on Lexis and Westlaw. Many countries have their own version of Lexis and Westlaw, such as Westlaw China or Lexis Middle East. Other countries have different commercial databases, like Germany's Beck Online or India's Manupatra and SCC Online. However, with a handful of exceptions, the UCLA Law Library does not subscribe to databases for non-U.S. countries and the U.S. versions of Lexis and Westlaw include only limited foreign materials. In most cases, you will need to access these laws on free websites and in print, just as you would access U.S. law if you did not have a Lexis or Westlaw subscription. 

Don't expect non-U.S. laws to be in English. Just as the U.S. does not translate all of its laws and legal websites into non-English languages, most other countries do not translate all of their laws and legal websites into English. If you are not fluent in the language of a country, do not expect to be able to do significant research into its laws.

Don't expect cases to be as important or available as they are in the U.S. Most countries outside the U.S. are civil law countries, which means they place greater reliance on statutes passed by the legislature and less reliance on cases. Although cases may still be cited, they are generally less important and often more difficult to find. See the box below for more details on different types of legal systems.

Types of Legal Systems

There are five main types of legal systems: common law, civil law, customary law, religious law, and mixed.  It is important to know which system you are working within because it affects the importance and availability of the various materials you will be researching.

  1. Common Law: The United States and most former British colonies have a common law legal system.  In common law systems, judicial precedents, i.e. case law, is a major source of law, although most common law systems also rely on statutes and regulations.  
  2. Civil Law: Most countries today are based on civil law systems.  Under a civil law system, most law is laid out in extensive codes and constitutions.  Although these types of countries do have judicial systems, their court cases are typically not considered binding law in the way they are under common law systems.
  3. Customary Law: Customary law is a type of (typically) unwritten law governing such areas as personal relationships and conduct.  No country has a solely customary law system, though it may play a role within some jurisdictions.
  4. Religious Law: Religious law tends to govern personal matters in the countries in which it operates.  Most religious legal systems operate alongside a civil or common law system.  Religious law is most prevalent in Islamic countries and Israel.
  5. Mixed Legal Systems: Some countries operate under mixed legal systems, incorporating some or all of the elements of the more strictly defined legal systems above. 

The CIA's World Factbook and the University of Ottawa's JuriGlobe both identify countries' legal systems: